RESUMO
BACKGROUND: Dysfunctional beliefs about the self are common in the development of depressive symptoms, but it remains unclear how depressed patients respond to unfair treatment, both dispositionally and neurally. The present research is an attempt to explore the differences in sensitivity to injustice as a victim and its neural correlates in patients with major depressive disorder (MDD) versus healthy controls. METHODS: First episodic, drug-naïve patients with MDD (n = 30) and a control group (n = 30) were recruited to compare their differences in victim sensitivity. A second group of patients with MDD (n = 23) and their controls (n = 28) were recruited to replicate the findings and completed resting-state functional magnetic resonance imaging (fMRI) scanning. Spontaneous brain activity measured by fractional amplitude of low-frequency fluctuation (fALFF) was used to characterize the neural correlates of victim sensitivity both in patients and in healthy controls. RESULTS: Higher victim sensitivity was consistently found in patients with MDD than healthy controls in both datasets. Multiple regression analysis on the fALFF showed a significant interaction effect between diagnosis and victim sensitivity in the right dorsolateral prefrontal cortex (DLPFC). CONCLUSIONS: The patients with MDD show higher sensitivity to injustice as a victim, which may be independent of their disease course. The MDD patients differ from healthy controls in the neural correlates of victim sensitivity. These findings shed light on the linkage between cognitive control subserved by the DLPFC and negative bias towards the self implicated by higher victim sensitivity among the depressed patients.
RESUMO
BACKGROUND: Injection drug users (IDUs) are at high-risk for acquiring human immunodeficiency virus, hepatitis C virus, and other infections, and delaying the switch from non-injection drug use to injection to drug use could reduce the spread of these infections. OBJECTIVES: To estimate the incidence of switching from non-injected heroin use (usually smoking or "chasing") to injection and to investigate the risk factors for this change. METHODS: We reviewed the socio-demographic and clinical data of 7305 heroin-dependent patients treated at a detoxification clinic of a university-affiliated psychiatric hospital in China from January 2000 to February 2009. RESULTS: Within 1 year, the majority of non-injection drug users (NIDUs) transitioned to IDUs (59.4% within 6 months and 76.7% within 12 months). Multiple logistic regression analysis showed that marital status, years of education, employment status, age at onset of heroin use, duration of drug abuse, and initial dose were associated with the switch from NIDU to IDU. Being married (B = -0.410, OR = 0.664), being employed (B = -0.243, OR = 0.784), and older age at onset (B = -0.040, OR = 0.961) were protective factors. More education (B = 0.120, OR = 1.128), longer duration of drug abuse (B = 0.010, OR = 1.010), and a higher dose at initial drug use (B = 0.234, OR = 1.264) were risk factors. CONCLUSIONS/IMPORTANCE: The study has identified several risk factors for the switch to injection among heroin users. Understanding these factors can help design new approaches to more specifically target high-risk populations and high-risk behaviors to delay or prevent the transition to injection.
